Coffee machine



FIG. 1 is a perspective view of the front and one side of the design;

FIG. 2 is a front elevational view of the design;

FIG. 3 is a rear elevational view of the design;

FIG. 4 is a plan view of the top of the design;

FIG. 5 is a plan view of the bottom of the design;

FIG. 6 is an elevational view of one side of the design; and,

FIG. 7 is an elevational view of the other side of the design.

The broken lines in the drawings are included for the purpose of illustration and form no part of the claimed design. 

The ornamental design for a “coffee machine,” as shown and described. 